1. Field of the Invention
This invention relates to a collapsible support for containers, semi-trailers, and the like, and particularly to a collapsible support or hitch having a supporting mounting plate or "fifth wheel" designed to engage a king pin or like of the containers, such as highway semi-trailers which are loaded upon railway cars or marine vessels for transport, the collapsible support having a low profile when it is in the storage position to accommodate the passage thereover of vehicles having low ground clearance, and to allow the stowage of cargo containers on top of the collapsed hitch. Particularly, the "fifth wheel" which is a king pin locking plate, is provided with an anti-jackknife device.
2. Description of the Prior Art
Many forms of anti-jackknive devices are available. For example, U.S. Pat. Nos. 3,430,986 and 3,985,369 describe the use of king pin locking plates in conjunction with modified apparatus of the tractors provided with brakeshoes and brakes for controlling the lateral movements of the trailer with respect to the tractor. Such arrangements are quite complex and expensive, and require either hydraulic or electrical power to control the braking application. Another anti-jackknive apparatus is described in U.S. Pat. No. 3,837,678, wherein a king pin locking plate is provided with a longitudinal recess for receiving a king pin on the trailer, which is then locked by an elongated locking member positioned in the recess and operated by a hydraulic assembly mounted on the trailer. Such anti-jackknive devices are satisfactory. However, they require that all trailers be equipped with a hydraulic arrangement activated by a power source on the tractor. Another form of anti-jackknive apparatus is described in U.S. Pat. No. 4,790,556, wherein a king pin locking plate has a longitudinal groove for receiving a king pin on the trailer, the king pin subsequently being secured by an anti-jackknifing abutment inserted into the recess and operated by a fluid-operated cylinder mounted on the trailer. This type of an arrangement is similar to the other discussed hydraulically operated device having the disadvantage of requiring a trailer to be equipped with a fluid cylinder for effecting proper closure of the king pin in the king pin locking plate.